The drills come at a time of heightened strain with self-ruled Taiwan, which Beijing claims as its own, following US President-elect Donald Trump’s telephone call with the island’s president that upset Beijing.

China's Kuznetsov-class aircraft carrier Liaoning sails the water in East China Sea on December 25, 2016.(Reuters file photo)

China’s sole aircraft carrier conducted drills in the South China Sea, the navy said, days after neighbouring Taiwan said the carrier and accompanying ships had passed 90 nautical miles south of the island amid renewed tension between the two sides.

The Soviet-built Liaoning aircraft carrier and accompanying warships sailed round the east coast of Taiwan in what China called a routine exercise complying with international law.

The carrier’s J-15 fighters conducted flight exercises in “complex sea conditions” on Monday, the People’s Liberation Army Navy said on its official microblog later on the same day.

The carrier group also ran helicopter exercises, it said, but did not give details on the exact location.

China claims most of the South China Sea through which about $5 trillion in ship-borne trade passes every year. Neighbours Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims.

The drills also come at a time of heightened strain with self-ruled Taiwan, which Beijing claims as its own, following US President-elect Donald Trump’s telephone call with the island’s president that upset Beijing.

Last month, China conducted its first ever live-fire drills using an aircraft carrier close to Korea and announced on December 25 that the Liaoning and its accompanying fleet will carry out what it called routine exercises in the Western Pacific.

Taiwan’s defence ministry on December 26 said the Liaoning and five accompanying ships had entered the top half of the South China Sea after passing south of Taiwan, and later docked at a base on China’s Hainan island.

The flotilla raised alarm in Japan when it steamed between the Japanese islands of Miyako and Okinawa.

Japan said one of its maritime self defence force ships and a P3C patrol aircraft had spotted six Chinese naval vessels including the Liaoning travelling through the passage, and they also scrambled jets after a helicopter which took off from a Chinese frigate flew near Miyako Island.

China has been angered recently by US naval patrols near islands that China claims in the South China Sea. This month, a Chinese navy ship seized a US underwater drone in the South China Sea. China later returned it.

China’s air force conducted long-range drills this month above the East and South China Seas which rattled Japan and Taiwan. China said those exercises were also routine.